Production of valuable hydrocarbons



Patented Dec. 30, 1947 PRODUCTION OF VALUABLE HYDROCARBONS Jacquelin E. Harvey, Jr., Washington, D. (1., and Robert H. White, J12, and Joseph A. Vaughan, Atlanta, Ga., assignors of one-half to Jacquelin E. Harvey, Jr., Washington, D. 0., and onehalf to Southern Wood Preserving Company, East Point, Ga., a corporation of Georgia No Drawing. Application October 7, 1944, Serial No. 557,726

12 Claims.

The present invention relates to the production of toxic oils employable as fungicides, insecticides, and for any other service to which toxic oils may be put, as for example burning oils, for it is well known that toxic oils make excellent fuels.

This application is a continuation-in-part of More especially the present invention relates to the catalyzed production of toXic oils from mixtures of petroleum fractions characterized by ring structure content. Among the preferred starting materials of the present process may be mentioned petroleum fractions recovered by extractive distillation and solvent extraction; also may be mentioned mixtures of petroleum fractions characterized by ring structure content as flowing from thermal and/or catalytic treatment, say for example, certain recycle oils.

An object of the present invention is the catalyzed production of toxic oils from the aforenamed petroleum fractions or others whereby to provide oils of the wood preservative type; another object of the present invention is the provision of wood preserving impregnants having boiling ranges and residues in accordance with published specifications and/ or in accordance with consumer preference; another object of the present invention is the cracking, reforming, modifying, converting and/or transforming of the named mixtures of hydrocarbons in the presence of suitable catalytic material whereby to induce commercially acceptable toxicity; still another object of the present invention is the unveiling of latent toxicity in mixtures of petroleum fractions having inherent but inhibited toxicity; yet another object of the instant invention is the provision in the overall beneficiated material of that percentage of newly induced fractions boiling below 210 C. which, in view of attendant reactions, is conducive to the induction of commercially acceptable toxicity in other fractions of the material under treatment; another object of the present invention is the induction of additional toxicity into fractional parts of the once beneficiated starting stock under specific controls of process variables; still another object of the present invention is the conversion of substantially non-toxic petroleum type aromatics into materials more closely approaching the highly toxic coal tar aromatic type, as more fully set forth in the following; another object of the present invention is the conversion of petroleum type aromatic material of relatively narrow boiling range into material of relatively wide boiling range more closely appreaching the characteristics of coal tar aromatics by a process carried on in the presence of catalytic material wherein the control is evidenced by, among other things, the percentage and specific gravities of newly formed aromatics found in certain fractions of the beneficiated feed stock.

One of the specific objects of the process of the present invention is the cracking, transforming, reforming, converting and/or modifying of relatively high boiling petroleum oils characterized by molecular structures of cyclic materials content having inherent but inhibited toxicity whereby to provide said molecular structures of cyclic materials content as materials exhibiting more pronounced toxic value.

In the past wood preservative oils of the high tem erature-coal tar derived type have been employed in quantities greatly exceeding the total of all other wood preservative oils. From the standpoint of availability of said coal tar as the parent product of wood preservative oils, it is annually produced in this country under normal conditions to the extent of five hundred million to six hundred million gallons. This quantity of coal tar is capable of yielding an amount of high- 1y effective wood preservative oil which would make this country self-sufficient in its oily wood preservative requirements. Howeven'due to the fact that when a wood preservative distillate (creosote) is recovered from coal tar there remains in the still a residue (pitch) which, at best, is a low priced product and which, at worst, is a seriously distress product to the end that at times it is placed in inventory rather than sold, the current method of processing coal tar leaves much to be desired. The net result of this situation obtaining is that the coal tar distiller usually confines himself to that distillation recovery of creosote which would correspond to the attending amount of pitch that he can market at a profit. Accordingly, over a period of years several hundred million gallons of creosote oil have been imported into this country. That such a situation should obtain is apparently a paradox in that we annually produce a quantity of hi temperature coal tar which if processed to yield creosote would make us self-suflicient in that requirement. A survey of this paradox is fully outlined in an address given by no less an authority than S. P. Miller, technical director, The Barrett Company, 40 Rector Street, New York city, before the Franklin Institute, Philadelphia, Pennsylvania, in December, 1932. The economics of coal tar have not materially changed since that date.

In view of the apparent inability of the coal tar industry to provide national needs of wood preservative oils, a strong incentive is given to groups processing other types of oil to invade the lucrative wood preservative market. At the present time many types of aromatic oils are produced by the petroleum industry, and the high boiling oils of aromatic content produced by this industry have for several years been tested for their wood preservative efficiency.

By the term petroleum aromatic as used herein and in the appended claims it is meant to include mixtures of petroleum fractions characterized by cyclic structure content and specifically various forms and types of naphthenes found in various mixtures of petroleum fractions, as for example monocyclic and polycyclic naphthenes.

The so-called petroleum aromatics which include the monocyclic and polycyclic naphthenes and unsaturated hydrocarbon have in the past been produced in very large quantities. However, very little work has been done on these materials. Such a fact is borne out on page 6.67, Reaction of Pure Hydrocarbons, Gustav Eglofi, Reinhold Publishing Corporation, 330 West 42nd Street, New York city, which states:

Despite the fact that naphthenes or cycloparaffines are available in enormous quantities, as shown by an estimate of 100,000,000 barrels present in the 1,498,000,000 barrels of crude oil which was the worlds production in 1934, comparatively little work of a pyrolytic nature has been performed on individual naphthene hydrocarbons or the cycloolefins.

Several oils of cyclic structure content produced by the petroleum industry have been inspected for their toxicity to Wood destroying fungi, among which may be mentioned a high boiling oil of cyclic structure content produced (1940) at the Wood River Refinery of the Shell Oil Company and which has the following inspection:

Gravity 10.8 Flash, P. M. C. C., "F 295 Flash, C. O. 0., F 290 Fixed Carbon, per cent 4.9

Pour Point, F -'10 B. S. & W., per cent by vol 0.1 S. U. Vis. 100 F 151 S. U. Vis. 210 F 41 S. F. Vis. 77 F 345 Carbon residue 6.8 Per cent aromatics and unsaturates 82.4 Sol. in CS2 99.8 Loss 50 grams, 5 hours, 325 F 8.9 Residue of 100 pene., per cent 37.5 A. S. T. M. distillation:

I. B. P., F 518 10% Rec. F 565 20% Rec. F 589 Rec. F 614 40% Rec. "F 637 50% Rec. "F 660 60% Rec. "F max 6'75 4 In the foregoing tabular data P. M. C. C. means Pensky-Martin Closed Cup; C. O. C means Cleveland Open Cup.

Upon evaluating the foregoing oil for its toxicity to wood destroying fungi (Madison 517), it was found that this oil did not totally inhibit the growth of the fungi named at a concentration of up to and including 10%. Madison 51'? is a strain of the fungus Fomes annosus.

It is now discovered that the oil above named or other oils of cyclic structure content produced by the petroleum industry can be increased in toxicity in accordance with the process of the instant invention.

According to the process of the present invention, petroleum oils of cyclic structure content are cracked, reformed, transformed, modified and/or converted to oils of a more toxic nature having characteristics more closely approaching those of high temperature coal tar preservative oils. Stated in another manner, the end product of the instant invention is acceptable to consumers of oily wood preservative impregnants and/or conforms in boiling range or aromatic content to previously published wood preservative specifications.

We have discovered that if the starting materials are subjected to a heat treatment in the presence of suitable catalysts, with or without the presence of a gas or gases of extraneous source, the While controlling process variables as to provide in the materials of the end product boiling between 210 C. and 355 C. a percentage of aromatics not substantially less than about 70%, the reformed, cracked, converted, transformed and/0r modified oil boiling between the temperatures above named will have a toxicity to wood destroying fungi closely approaching or equalling the toxicity of high temperature coal tar or its wood preservative derivatives, provided (1) the specific gravities of the overall fractions within the 2lO-355 C. out of the beneficiation fall about within the limits shown in the appended tabular data:

Or (2) specific gravities of the aromatics in the overall fractions of the 210355 C. cut of the beneficiated material fall about within the limits shown in the appended tabular data:

Fraction Low Limit High Limit 0.913 1. 0430 0. 935 l. 0600 0.973 1. 0933 l. 027 l. 1215 Various catalysts assist in the cracking, reforming, transforming, modifying and/or converting of the named starting petroleum stocks whereby to provide materials of induced toxic properties. Several catalysts have been found to be especially eifective. Among these highly effective catalysts may be mentioned the oxides and sulfides of metals, as well as the carbonates and the metals themselves. Cellulosic materials and carbon, activated or otherwise, may be used with advantage.

Using certain charging stocks, siliceous materials, halogens, halids and derivatives thereof, including specifically substitution and addition products thereof, as for example and specifically substitution and addition products of said derivatives, have been found to give especially beneficial results.

When oxide, sulphide, cellulosic or carbonaceous catalysts are employed, they may be used in a comminuted form, and the selected one is added to the feed stock in the amount of between one half and ten percent, and preferably between two and eight percent; or suitable of the named catalysts may be deposited on carriers, inert or otherwise. In the event our process is practiced in a more or less continuous operation, and the feed stock is passed through a reaction chamber, the stipulated percentage of catalyst in comminuted form may be added. In some instances, the reaction chamber may be filled with cellulosic materials, activated carbon, or oxides or sulphides of heavy metals deposited on carriers, and

1 the feed stock caused to pass between the interstices of the catalyst units. When halogens, halids, or derivatives thereof are employed as the catalyst, they are used in an amount selected between the limits of 0.001 and 10.0 percent, and preferably between 0.01 and 5.0 percent.

The catalysts employed in the instant process are reforming catalysts. a reforming catalyst is meant a catalyst adapted to favorably influence the reactions that are conducive to the induction of toxicity, be the reactions those of addition, subtraction or substitution.

The following examples will serve to illustrate several modes of practicing the process of the present invention.

Example 1.A mixture of petroleum fractions boiling preponderantly above 270 C., having but slight growth inhibition to wood destroying fungi,

whose fractions 235-270 C., 270-315 C. and 315-355 C. have respectively the following specific gravities: 0.9697, 0.9989 and 1.036, is charged to a high pressure rocking autoclave, Silica gel in the amount of of the charging stock is added as catalytic material. The contents of the autoclave are brought up to a temperature of 490 C. and held there for a period of one hour, the meanwhile keeping the contents of the autoclave in a state of agitation. At the end of the named treatment period the beneficiated stock is cooled and inspected and is found to have (1) more than 10% newly formed materials boiling below 210 C., and (2) an overall toxicity closely approaching or equalling the toxicity of certain high temperature coal tar wood preservatives.

Inspection of the beneficiated material discloses matters shown in the appended tabular data:

Toxicity S Total Inpeglfic Percentage Fraction Gravity o1 lbl i011 of Aromatics Point) Aromatics 0. 50 0. 8518 40. 0 0. 005 0. 9514 100. 0 0. 010 0. 9949 100. 0 0. 500 l. 0167 100. 0 3l5355 C 5. 000 1.0554 100.0

Entire five iractions approx. 0.050.

The total inhibition point (toxicity test) above noted is expressed as the percent of the preserva- By the expression found by controlling the process variables as to provide in the 0-355 C. or 210-355 C.cut of the beneficiated material (1) specific gravities in aromatics in fractional parts of said out which fall between the limits previously stated, and/or (2) specific gravities in overall fractions of the named cut whichfall between the limits stated in the foregoing, provided at least about 70% of aromatics appear in said cut of the beneficiation, that'this is a guarantee of, and a test for, induction of toxicity to wood destroying fungi in .the named out which closely approaches or equals the toxicity of certain high temperature coal tars or their preservative derivatives. The controls above named, either or both, (viz: (1) or (2) supra) are practices by which suificient side chains or fractional parts thereof may be removed from the highly toxic ring nuclei to insure in the beneficiated material acceptable toxicity to the wood preserving industry.

By processing the starting feed stock of the present example in the presence of the named catalytic material, a crude petroleum stock whose toxicity to wood destroying fungi is not acceptable to the wood preservin industry is at least partially converted into a material which closely approaches or equals the toxicity of conventional high temperature coal tar or certain of its oily wood preservative derivatives.

The beneficiated feed stock is fractionated by distillation to recover as a distillate a preservative wood impregnant of induced toxic properties having 5% distilling below 210 C., more than 20% distilling above 315 C., and less than 10% residue above 355 C. It is of especial importance that, the newly formed preservative oil which flows from our catalytic process has at least about 15-20% residue above 315 C. for it is on these materials boiling above 315 C., among others, that our new oil depends for its permanency after impregnation in the wood.

The materials of induced toxic properties as flowing from our process which employs catalytic is desired to provide a preservative impregnant complying with previously published specifications or of consumer preference, a wood preservative oil may be segregated from the treated feed stock as a stabilized residual, distillate or extract, and in the event the extract has non-permissible low boiling ends the extract may be stabilized to the necessary extent by the removal of low boiling ends; or the preservative oil may be recovered from the extract as a distillate.

As illustrative of preservative wood impregnants of the oil derived type that have met with consumer acceptance, and which may be segregated from the overall beneficiated material of the instant process, the following tabular data show several previously published wood preservative specifications which in the past have been Woon Pnnsmrva'rrvn Imrnrzcmnrs Specifications 1. American Wood Preservers Association a. Up to 210 0., not more than b. Up to 235 0., not more than 25% 2. American Wood Preservers Association a. Up to 210 C., not more than 1% b. Up to 235 0., not more than 0. Up to 355 0., not less than 65% 3. American Wood Preservers Association a. Up to 235 0., not more than 1V2% 1). Up to 300 0., not more than 16 /2% 0. Up to 355 0., not less than 45% 4. American Wood Preservers Association (1. Up to 210 0., not more than 8% 12. Up to 235 0., not more than 35% 5. American Wood Preservers Association (1. Up to 210 C., not more than 10% b. Up to 235 C., not more than 40% 6. American Wood Preservers Association a. Up to 210 C., not more than 5% b. Up to 235 C., not more than Prussian Ry.

a. Up to 150 0., not more than 3% b. Up to 200 0., not more than 10% l 0. Up to 235 0., not more than 25% 8. National Paint Varnish 8: Lacquer Association a. 5% at 162 C. b. 97% at 270 C. 9. Southern Pine Shingle Stain Oil a. 5% at 137 C. b. 95% at 257 C. 10. Neville Shingle Stain Oil a. I. B. P., 150 C. b. 5% at 205 C. c. 95% at 292 C. 11. Carbolineum 270 C., I. B. P,

Example 2.-A petroleum aromatic oil having 2% distilling below 235 C., and boiling preponderantly between 235 C. and 355 C. is charged to a high pressure rocking autoclave under a cold hydrogen pressure of 500 pounds. 5% of a catalyst (based on the feed stock) consisting of molybdenum sulfide deposited on an inert carrier is the catalyst employed. The contents of the autoclave are brought up to a temperature of 490 C. and held at that temperature for one hour and 10 minutes. The contents of the autoclave are mechanically agitated during the heating period. At the end of the treatment time above specified the beneficiated oil is allowed to cool,

and inspection reveals that the 210-355 C. out is substantially as toxic as conventional high temperature coal tar creosote.

The 210-355 C. out of the heat treated oil has the following inspection:

Toxicity Overall Fraction (Total In- Specific Percentage hibition Gravity of of Aromatics Point) Fraction 210-235 O 0.005 0. 9514 100.0 235-270 C 0. 010 0. 9949 100.0 15 C 0.500 1.0167 100.0 315-355 C 5. 000 1. 0554 100.0

All four fractions approx. 0.050.

sufiicient reforming, cracking, modifying, transforming and/or converting has been accomplishcd to insure the materials in the beneficiation boiling between the temperatures named having a toxicity to wood destroying fungi comparing favorably with that found in high temperature coal tar preservative impregnants.

Example 3.When processing the starting stocks in the presence of catalytic material, with or without the inclusion of a gas of extraneous source, as disclosed in Examples 1 and 2, it is found that the materials boiling below and above 270 C. have a relatively high and low toxicity, respectively. It is of especial importance that the reformed materials boiling above 270 C. have as high a toxicity as possible to wood destroying fungi for the superior reason that these high boiling materials have a toxicity blanketing eiiect on the lower boiling materials of highest toxicity. By retreating the once processed material boiling above 270 C., we have discovered that additional toxicity may be induced. Hereinafter we outline a typical practice of this phase of our invention.

The starting material is charged to a rocking autoclave under a cold water gas pressure of 500 pounds per square inch. One hundredth of one percent of iodoform, based on the feed stock, is employed as catalytic material. The temperature is then raised to 500 C. and held at that heat tone for one hour. The partially beneficiated material is allowed to cool to atmospheric temperature, and cut at 270 C. to provide a low boiling portion of relatively high toxicity and a high boiling portion of relatively low toxicity. The high boiling portion is charged back to the autoclave under a cold water gas pressure of 500 pounds per square inch. The contents of the autoclave are heated to a temperature of 475 C. and there held for a period of 45 minutes. The autoclave which is of the rocking type is allowed to reach atmospheric temperature and the contents discharged. The once and twice treated materials are commingled and are found to have in that portion boiling between 210 C. and 335 C. a percentage of aromatics in excess of 70%. The specific gravities of the aromatics in question fall between the limits shown in the foregoing tabular data, and the specific gravities of overall fractions in the 2l0355 C. out fall within the limits previously noted.

The beneficiation is fractionally distilled to provide a wood preserving impregnant as a distillate which boils preponderantly between 210 C. and 355 C. and has 30% residue above 315 C. The segregated wood preservative has induced toxicity which closely approaches that found in certain high temperature coal tar wood preservative materials.

Instead of cutting the primary beneficiation at 270 C., the cut may be made at any other temperature, say at 280 0., 300 C. or 315 C., above or below, whereby to provide the low boiling portion as a material of relatively high toxicity and the high boiling cut as a material of relatively low toxicity. The high boiling portion is then treated at a temperature falling within the limits elsewhere herein disclosed.

We have found when practicing our two-step process. the first step at least being carried on in the presence of a catalytic material, that by providing a total treatment period not in excess of about two hours, acceptable toxicity closely approaching or equalling that of high temperature coal tar preservative products may be provided. As illustrative of this mode of practice, but without inferring treatment period limitations, a period not in excess of one hour may be employed in the primary step, and a period not in excess of 30 or 40 minutes, more or less, may be employed in the secondary step which retreats the higher boiling segregation. Such treatment periods have been found to give the desired results, although other periods of treatment for the two steps, the total of which falls below about two hours, may be practiced.

Example 4.-A petroleum aromatic oil distilling below 235 C. and having distilling above 315 C., an aromatic and unsaturated content of 70%, a specific gravity of aromatics of 1.01 in the 270-315 C. fraction is charged to a high pressure rocking autoclave. Activated carbon in the amount of 10%, based on the feed stock, is employed as the catalyst, The contents of the autoclave while in a state of agitation are brought up to a temperature of 460 C. and there held for a period of one hour while maintaining a pressure of 10.00 pounds per square inch. Thereafter, and without substantially lowering the temperature, the contents of the autoclave are held under a pressure of 400 pounds for a period of minutes. At the end of the named second period the beneficiation is cooled and inspected, and is found to have in excess of 70% aromatics in the materials boiling between 210 C. and 355 C., and the fractional parts of the 210-355 C. out have aromatics whose specific gravities fall within the limits noted in tabular data previously shown.

When the beneficiated stock is fractionallydistilled to recover the 210-355 C. cutas an oil of the wood preservative type, it is found that the cut named has a toxicity to Wood destroying fungi comparing favorably with that toxicity found in high temperature coal tar creosotes.

In the two-step operation disclosed in the present example we have found that a period not in excess of about one hour is suitable for the primary step. Dependent upon the temperature selected within the range hereinafter disclosed, periods of 20, 30 or minutes, more or less, are acceptable. In the secondary step of this mode of practicing the present process, we have found that a period not in excess of about one hour is sufi'icient to induce the desired qualities and characteristics in all starting feed stocks that we have examined. With some feed stocks periods of 20, 30 or 40 minutes, more or less, are satisfactory in the secondary step. When employin in the first stage a relatively high temperature within the range elsewhere herein disclosed, and a relatively high pressure drop in the second stage, a relatively short period of treatment in the second stage will provide the desired percentage and specific gravities of aromatics. We; have discovered that the relationship of the high and low pressure steps may vary over relatively broad limits, as for example, the first step may be carried out at very high pressures and the secondary step at a pressure only slightly above atmospheric.

Viewed broadly this phase of practice of our invention is not circumscribed by any definite pressures in the high and low pressure steps, but

rather turns on employing a relatively high pressure in the first stage and relatively low pressure in the second stage Example 5.-The Shell aromatic oil noted previously is charged to a high pressure rocking autoclave. The catalyst is the co-precipitated oxides of chromium and copper. Hydrogen is pumped into the autoclave to an upper pressure of 300 pounds per square inch. The contents of the autoclave are heated to a temperature of 460 C. and held at that heat tone for a period of 40 minutes. Thereafter the temperature is raised to 500 C. and held at that heat tone for a period of 30 minutes. The beneficiated material is cooled and inspected and is found to have more than 10% of newly formed fractions boiling below 210 C., and in the materials boiling between 210-355 C. in excess of aromatics. The specific gravity of aromatics in fractional parts of the 210355 C. out of the treated stock falls between the limits noted in tabular data previously shown. A toxicity evaluation of the processed oil boiling between 210-355 C. indicates that only about 0.5% is required for total inhibition of growth of wood destroying fungi.

We have found that when practicing our invention with a relatively low temperature step and a subsequent relatively high temperature step, both steps being carried out in the presence of catalytic material, the temperatures in both steps being selected between the limits of about 350- 600 C., optimum conditions are secured by providing a treatment in each step of not in excess of about one hour. If relatively high temperatures within the limits named are employed in the two-step process of dissimilar temperatures, relatively short periods in the two steps are possible, and we have found that under very severe thermal conditions within the limits named, periods of 10, 20 and 30 minutes in each step, more or less, suffice to induce the desired characteristics.

Viewed broadly, this phase of our invention is not circumscribed by any definite time period, other than the upper limit above stated, but rather turns on the correct coordination of a relatively low temperature step and a relatively high temperature step whereby to provide (1) the desired percentage and specific gravity of aromatics, or (2) the desired percentage of aromatics and specific gravity of overall fractions in the end product, which thing or things in turn insure induction of toxicity closely approaching or equal ling that Of high temperature coal tar preservative wood impregnants.

Instead of practicing our process in a once through treatment as disclosed in Example 1, especial toxicity induction benefits fiow from dividing the beneficiation into a relatively low boiling portion and a relatively high boiling portion, and subsequently retreating separately the two fractions. The two fractions may be treated at similar or dissimilar temperatures within the range elsewhere herein disclosed. When the retreated fractions are commingled it will be found that they have a toxicity in excess of the once treated material.

In lieu of retreating the high and low boiling portions, the low boiling portion may be retreated and then commingled with the once treated high boiling portion to provide a comminglement having a toxicity in excess of the once treated oil.

Another mode of practicing our invention resides in treating the petroleum aromatic containing oil in the presence of benzene, toluene, naphthalene or their derivatives. As exemplifying this mode of practice, 50 parts of the petroleum aromatic oil and 50 parts of benzene are commingled and charged to a rocking high pressure autoclave. Based on the commingled oils, 10% of silica gel is added as catalyst. The comminglement is then, for example, treated as in Example 1. The resultant alkylated benzene is 11 then removed by distillation. Upon inspection, it is found that the treated petroleum aromatic oil has a percentage of aromatics not lower than 70% and the specific gravity of the aromatics in fractional parts of the 210-355 C. out fall between the limits noted in the tabular data previously shown. The comminglement of 50 parts of petroleum aromatic with 50 parts of benzene is for purposes of illustration only inasmuch as other percentages may be used, say for example, parts of benzene and 75 parts of petroleum aromatic.

At times we have found it advantageous to shock cool our treated feed stock after completion of the processing period to a temperature below 250 C., and preferably below 200 C. The shock cooling may be accomplished by contacting the processed oil with a relatively cool oil, and the relatively cool oil may conveniently be the preservative oil previously made by the process. This shock cooling method is to be, in one mode of operation, specifically read into all examples.

In previous examples, the overall feed stock has been shown as being treated. In lieu of this, the

raw feed stock may be divided into two or more fractions and separately treated. As an example, the feed stock may be divided into a relatively low boiling fraction and a relatively high boiling fraction. The low boiling fraction is then treated at a relatively high temperature within the range herein disclosed elsewhere, and the high boiling fraction is treated at a relatively low temperature within the stated range, the periods of treatment in this instance being the same as taught previously for high and low boiling cuts, beneficiated or otherwise. If three cuts of the raw feed are made, the lowest boiling fraction is treated at the highest temperature, the intermediate fraction at an intermediate temperaure and the highest boiling fraction at the lowest temperature. This teaching applies to any number of cuts into which the feed may be divided.

Viewed broadly, the product of the instant process is a transformed, reformed, modified and/or converted petroleum oil boiling preponderantly between 210-355 C. with at least about 15-20% material boiling above 315 C., having at least about 70% aromatics in the materials boiling between 210 C. and 355 C., and in the fractional parts of the oil boiling between 210-355 C., certain specific gravities as taught in the foregoing.

The pressures of the process of the present invention are in excess of atmospheric and may be as high as practicable. When inducing toxicity into petroleum oils in accordance with our process, temperatures of between 350 C. and 600 C. may be employed, however, our preferred range is between 400 C. and 500 C.

Our process may be carried on with or without the presence of a gas of extraneous source. At times. and when employing certain petroleum feed stocks, it is highly beneficial to employ extraneous gases. Among such gases may be mentioned hydrogen, water gas and hydrocarbon gases.

Either liquid or vapor phase may be practiced in our process and this disclosure is specifically to be read into all examples. Non-inventive skill will enable those acquainted with the art to coordinate temperatures within the range disclosed with relatively moderate pressures in order to secure vapor phase practice. When employing vapor phase operation and processing any of the feed stocks previously described, definite periods falling within the limits previously disclosed will provide specific gravities and aromatic percentages shown in the foregoing.

One phase or various phases of one example may be substituted for a phase or various phases of another example where the substitution is obviously workable.

Intermittent or continuous operation, or a combination thereof, may be practiced in the present process, and those skilled in the art can apply this to our invention without recourse to inventive skill.

Minor changes within the scope of the appended claims may be made Without departing from the spirit of the invention.

We claim:

1. In the induction of toxicity to wood destroying fungi into a mixture of petroleum fractions boiling preponderantly above 270 C., characterized by inherent but inhibited toxicity and a substantial percentage of materials of ring structure content, the process which comprises: subjecting said material at superatmospheric pressure in the presence of a catalytic material to a temperature selected between the limits of about 350-600 0.; unveiling toxicity in the material under treatment by carrying on the process for a period not substantially in excess of about two hours, the period being so selected with reference to the chosen temperature and pressure as to jointly provide in the beneficiation newly formed materials boiling below 210 C., a percentage of aromatics in the fractions boiling between 210-355 C. not substantially less than about 70%, and a specific gravity in the aromatics above named falling between the limits shown in the appended tabular data:

whereby to provide a material of induced toxic properties.

2. The process of claim 1 with inclusion of segregating from the beneficiated material an oil of the wood preservative type characterized by induced toxic properties, boiling preponderantly between about 210-355 C. and having at least 15-20% residual materials boiling above 315 C.

3. In the induction of toxicity to wood destroying fungi into a mixture of petroleum fractions boiling preponderantly above 270 C., characterized by inherent but inhibited toxicity, a substantial percentage of materials of ring structure content and an end boiling point in excess of 355 C., the process which comprises: partially unveiling toxicity in the named materials by subjecting same at superatmospheric pressure in the presence of a catalytic material to a temperature selected between the limits of about 350-600 C. whereby to provide an overall beneficiation having relatively high and low toxicity in the materials boiling below and above 270 C., respectively; segregating all of the materials of relatively low toxicity boiling above 270 C. and subjecting same at superatmospheric pressure to a temperature selected between the limits above named; unveiling toxicity in a relatively high degree in the materials under treatment by carrying on the process in both steps of treatment for periods totalling not in excess of abou two hours, the periods being so selected with reference to the chosen temperatures and pressures as to pro- Fractions Low Limit High Limit 210235 C O. 9514 1. 0430 235-270 C O. 9949 1. 0606 Till-315 C. 1. 0167 1. 0933 315-355 C 1. 0554 1. 1285 whereby to provide materials of induced toxic properties; and commingling the segregations above named whereby to provide an overall oil of induced toxic properties which contains fractions essential in an acceptable preservative impregnant.

4. The process of claim 3 with inclusion of segregating from the beneficiated material an oil of the wood preservative type characterized by induced toxic properties, boiling preponderantly between about 210 C. and 355 C. and having at least about 15-20% residual materials boiling above 315 C.

5. In the induction of toxicity to wood destroying fungi into a mixture of petroleum fractions boiling preponderantly above 270 0., characterized by inherent but inhibited toxicity and a substantial percentage of materials of ring structure content, the process which comprises: subjecting said material at a relatively high pressure in the presence of a catalytic material to a temperature selected between the limits of about 350600 C. for a period not in excess of about one hour; thereafter subjecting the heat treated material sub-' stantially in entirety to a relatively low pressure without a substantial reduction in temperature for a period not in excess of about 30 minutes; unveiling toxicity to a relatively high degree in the material under treatment by carrying on the twostage process for periods falling within the limits above named, the periods being so selected with reference to the chosen temperature and pressure as to jointly provide newly formed material boiling below 210 0., a percentage of aromatics in the fractions boiling between 210355 C. not substantially less than about 70%, and a specific gravity in the aromatics above named falling between the limits shown in the appended tabular data:

whereby to provide a material of induced toxic properties.

6. The process of claim 5 with inclusion of segregating from the beneficiated material an oil of the wood preservative type characterized by induced toxic properties, having at least about 15-20% residual material boiling above 315% C., and boiling preponderantly between about 210 C. and 355 C.

'7. In the induction of toxicity to wood destroying fungi into a mixture of petroleum fractions boiling preponderantly above 270 (3., characterized by inherent but inhibited toxicity and a substantial percentage of materials of ring structure content, the process which comprises; subjecting said material at superatmospheric pressure in the presence of a catalytic material to a relatively low temperature selected between the limits of about 350-600 C. for a period not in excess of about one hour; thereafter subjecting the heat treated material substantially in entirety at super-atmospherio pressure to a relatively high temperature for a period not substantiallyin excess of about one hour; unveiling toxicity to a relatively high degree in the material under treatment by carrying on the two-stage process for periods falling within the limits above named, the periods being so selected with reference to the chosen temperatures and pressures in the two steps as to jointly provide newly formed materials boiling below 210 0., a percentage of aromatics in the fractions boiling between 210355 C. not substantially less than than about and a specific gravity in the arcmatics above named falling between the limits shown in the appended tabular data:

whereby to provide a material of induced toxic properties.

8. The process of claim 7 with inclusion of segregating from the beneficiated material an oil of the wood preservative type characterized by induced toxic properties, boiling preponderantly between 210" C. and 355 C., and having at least about 15-20% materials boiling above 315 C.

9. The process of claim 1 in which the catalytic material is selected from the group consisting of oxides and sulfides of metals.

10. The process of claim 3 in which the catalyst is a siliceous containing material.

11. The process of claim 5 in which the catalyst employed is active carbon.

12. In the induction of toxicity to wood destroying fungi into a mixture of petroleum fractions boiling preponderantly above 270 0., characterized by inherent but inhibited toxicity and a substantial percentage of materials of ring structure content, the process which comprises: subjecting said material at superatmospheric pressure in the presence of a catalytic material to a temperature selected between the limits of about 400-600 0.; unveiling toxicity in the material under treatment by carrying on the process for a period not substantially in excess of about two hours, the period being so selected with reference to the chosen temperature and pressure as to provide a toxicity to wood destroying fungi between 0.050 and 0.500 in the beneficiated materials having boiling points falling between 210-355 C., an initial boiling point at least as low as about 270 C., an end boiling point at least as high as about 355 C. and a. specific gravity in overall fractional parts of the overalloil falling between the following limits:

Fraction Low Limit High Limit J ACQUELIN E. HARVEY, JR. ROBERT H. WHITE, JR. JOSEPH A; VAUGHAN.

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